Composite truss joist with lower chord bearing



6 A. L. TROUTNER 3,336,706

COMPOSITE TRUSS J OIST WITH LOWER CHORD BEARING Filed July 28, 1966 Arfhur L.Trou+ner B INVENTORY United States Patent Ofi ice 3,336,706 Patented Aug. 22, 1967 3,336,706 COMPOSITE TRUSS JOIST WITH LOWER CHORD BEARING Arthur L. Troutner, Boise, Idaho Filed July 28, 1966, Ser. No. 568,635 6 Claims. (Cl. 52261) This invention is a continuation-in-part of my co-pending application Ser. No. 334,705, filed Dec. 31, 1963 for Long Span, High Load, Composite Truss Joist.

This invention relates to truss joists of the class comprising vertically spaced chords interconnected by a plurality of link members arranged in zig-zag disposition between the chords.

It is the general object of the present invention to provide a composite truss joist of the class described wherein the lower chord of the truss joist bears against the bearing walls or other structural supports, cantilevering the truss joist outwardly beyond the plane of the latter and making possible interesting and useful roof and skylighting arrangements in structures incorporating the truss joist. Such a truss joist is termed herein a truss joist with lower chord bearing.

It is another object of the present invention to provide a truss joist with lower chord bearing which is strong, capable of supporting heavy loads over long spans and stable in its assembled working condition.

Still another object of the present invention is to provide a composite truss joist which may be assembled from ordinary lumber and metal tubing; which is light in weight; which may be prefabricated in assembly line pro duction at the plant; which may be transported with facility; and which may be erected rapidly on the building site without the necessity of using power equipment.

Still a further object of the present invention is the provision of a composite truss joist which may be mounted on various types of bearing support members such as bearing walls of concrete, wood or masonry and cross beams of wood or steel.

In the drawings:

FIG. 1 is a fragmentary view in side elevation of the herein described composite truss joist illustrating its lower chord bearing application; and

FIGS. 2, 3 and 4 are fragmentary detail views in side elevation, end elevation and plan, respectively, further illustrating the construction of the herein described truss joist, FIG. 3 being partly in section to reveal the connecting means employed for securing together the elements of the truss joist.

As shown in FIG. 1, the truss joists of my invention are supported in parallel spaced arrangement between a pair of support members such as hearing walls 10. The bearing walls may be of wood, concrete or masonry. A bearing plate 14 is fixed to the upper surface of each bearing wall. This may comprise a piece of lumber of suitable dimensions, as a 2 x 4 or 2 x 6.

Each truss joist is composed of an upper chord, indicated generally at 16, and a lower chord, indicated generally at 18. The length of the chords is at least equal to the distance between spaced bearing walls 10. Preferably, in this embodiment of truss joist, the length of the chord is greater than the distance between the spaced bearing walls, so that the resulting truss joist will over hang the bearing walls by a predetermined amount. This makes possible cantilevered constructions of interest in producing roof or wall overhangs as well as skylighting and other effects of design and functional interest.

To lend strength to the truss joist, each of chords 16, 18 is a composite of two structural pieces placed side by side, parallel to each other, and spaced apart horizontally to provide an intermediate space of sufficient width to accommodate the structural links by means of which they are interconnected.

Thus upper chord 16 may be a composite of 2 x 6 pieces 22, 24 placed on edge. Similarly lower chord 18 may be a composite of 2 x 4 pieces 26, 28 placed on edge.

Upper chord 16 and lower chord 18 are interconnected by a lacing of terminal link members 30 and central link members 32 arranged in zig-Zag fashion. Each link member may comprise a metal tube having transversely perforated flattened ends. The latter are of such thickness that when overlapped they may be inserted in the space between the pieces comprising each chord.

At spaced, ofiset intervals the upper and lower chords are cross bored to form openings which register with the perforations through the flattened ends of the link members. Pins 34 are inserted through the registering openings to interconnect the link members and chords as well as to secure together the component pieces of each chord. They are locked in place by press-on, friction grip washers 36.

The terminal ends of terminal link members 30 are inserted between structural pieces 26, 28 comprising lower chord 18. They are secured to the pieces and to the supporting structure in a manner which-makes it possible to achieve the purposes of the invention.

The means employed for this purpose comprise pairs of standards adapted to be mounted one pair on each of the bearing walls at each of the bearing points of the lower chord.

Thus each standard 40 may comprise an angular member, preferably T shaped in cross section and having a base section 42, the under surface of which lies flush against the upper surface of bearing plate 14. A vertical section 44 extends upwardly from base section 42, centrally thereof. Its inner face lies flush against the outer side face of one or the other of structural pieces 26, 28.

The inner portion of base section 42 underlies the respective structural piece with which it is associated. The outer portion of the base section may be perforated and affords means for securing the standard to the underlying bearing plate 14 by means of screws 46 or other suitable fasteners.

Means also are provided for securing the standards to the chord components in interlocked structural relation.

To this end the upright sections 44 of each pair of the standards contain openings which register with each other as well as with the openings through structural pieces 26, 28 and through the flattened end of link 30. A hollow cylindrical pin 50 of heavy wall, high strength material is fitted snugly within the registering openings through structural pieces 26, 28 and the flattened end of link 30. A bolt 52 dimensioned for a snug fit within the bore of pin 50 is inserted through all of the registering perforations and through the bore of pin 50. It is locked in place releasably by means of nut 54.

In this manner the vertical load of the truss is transferred through link 30, hollow pin 50, bolt 52 and standards 40 to the support provided by bearing plate 14. This makes it possible to locate the truss joist with lower chords 18 bearing against the bearing walls and with the outer ends of the truss joist extending outwardly beyond the plane of the bearing walls in the desired cantilevered arrangement.

Having thus described my invention, I claim:

1. A composite truss joist comprising (a) two vertically spaced chords dimensioned to span two horizontally spaced bearing walls with the lower chord in bearing contact therewith,

(b) each chord comprising two juxtaposed structural pieces placed side by side parallel to each other,

(c) a plurality of links arranged in zig-zag relation between the chords with the ends of adjacent links overlapped and extending between the structural pieces comprising the chords, the terminal ends of the terminal links being inserted between the structural pieces comprising the lower chord,

(d) there being registering openings through the structural pieces and the link ends,

(e) pin means penetrating the registering openings, securing the links to each other and to the structural pieces,

(f) two pairs of standards adapted to be mounted one pair on each of the bearing walls, outside the structural pieces comprising the lower chord,

(g) first securing means for securing the standards to the bearing walls, and

(h) second securing means securing the standards to the structural pieces.

2. The composite truss joist of claim 1 wherein the standards are shaped angularly of flat sections, one section lying flush against a side face of one of the structural pieces comprising the lower chord and another section lying fiush against the surface of the bearing wall.

3. The composite truss of claim 2 wherein the standards are T shaped in cross section.

4. The composite truss of claim 2 wherein the standards are T shaped in cross section and wherein the first securing means for securing the standards to the bearing wall comprise threaded interengaging means penetrating the bearing wall and the standard section in contact therewith.

5. The composite truss of claim 2 wherein the standards are T shaped in cross section and wherein the second securing means for securing the standards to the structural chord pieces comprise bolt means penetrating the pieces, the terminal end of the terminal link, and the sections of the standards which are flush against the outer surfaces of the pieces.

6. The composite truss of claim 2 wherein the standards are T shaped in cross section and wherein the second securing means for securing the standards to the structural chord pieces comprise hollow pin and bolt means penetrating the pieces, the terminal end of the terminal link, and the sections of the standards which are flush against the outer surfaces of the pieces.

References Cited UNITED STATES PATENTS 1,813,373 7/1931 Wooldridge 52-693 2,864,471 12/1958 Williams 52-693 3,078,970 2/ 1963 Black 56-693 JOHN E. MURTAGH, Primaiy Examiner.

R. A. STENZEL, Assistant Examiner. 

1. A COMPOSITE TRUSS JOIST COMPRISING (A) TWO VERTICALLY SPACED CHORDS DIMENSIONED TO SPAN TWO HORIZONTALLY SPACED BEARING WALLS WITH THE LOWER CHORD IN BEARING CONTACT THEREWITH, (B) EACH CHORD COMPRISING TWO JUXTAPOSED STRUCTURAL PIECES PLACED SIDE BY SIDE PARALLEL TO EACH OTHER, (C) A PLURALITY OF LINKS ARRANGED IN ZIG-ZAG RELATION BETWEEN THE CHORDS WITH THE ENDS OF ADJACENT LINKS OVERLAPPED AND EXTENDING BETWEEN THE STRUCTURAL PIECES COMPRISING THE CHORDS, THE TERMINAL ENDS OF THE TERMINAL LINKS BEING INSERTED BETWEEN THE STRUCTURAL PIECES COMPRISING THE LOWER CHORD, (D) THERE BEING REGISTERING OPENINGS THROUGH THE STRUCTURAL PIECES AND THE LINK ENDS, (E) PIN MEANS PENETRATING THE REGISTERING OPENINGS, SECURING THE LINKS TO EACH OTHER AND TO THE STRUCTURAL PIECES, (F) TWO PAIRS OF STANDARDS ADAPTED TO BE MOUNTED ONE PAIR ON EACH OF THE BEARING WALLS, OUTSIDE THE STRUCTURAL PIECES COMPRISING THE LOWER CHORD, (G) FIRST SECURING MEANS FOR SECURING THE STANDARDS TO THE BEARING WALLS, AND (H) SECOND SECURING MEANS SECURING THE STANDARDS TO THE STRUCTURAL PIECES. 